1. Field of the Invention
The present invention relates to a nozzle cap, spring valve and body assembly for mounting to a trigger sprayer which is used in dispensing liquid in a spray mode or a jet mode and for containing the liquid in an OFF mode.
2. Description of the Related Art
A variety of simple and inexpensive hand-operated trigger sprayers have been proposed which include means for coupling to a container from which a liquid is to be dispensed under pressure. Such a trigger sprayer includes a trigger which is intended to be moved manually to operate a pump piston within a cylinder in a body of the trigger sprayer, usually against the force of a return spring, so that liquid may be pumped from the container and dispensed through an ejection nozzle or outlet orifice of the trigger sprayer.
To meet consumer demands for convenience it has been found to be highly desirable that the nozzle provide varying discharge patterns such as a conical spray pattern and a stream pattern. It is further preferable that the nozzle assembly not only be able to accommodate a stream mode or conical spray mode of operation in a highly reliable fashion, but that it also conveniently engage into an OFF mode position to contain the liquid in the dispenser to prevent leakage or inadvertent discharge of the liquid and to promote easy storage of the container of liquid with the trigger sprayer mounted thereon by the ultimate consumer.
To minimize cost, the various parts of the prior art trigger sprayers are increasingly made of plastic resins suitable for injection molding. Further, it has been found to be highly desirable that the design of the trigger sprayer be simplified such that the number of separately molded parts are minimized and so that the assembly of the parts may be mechanized at a minimum of cost and with maximum economy.
Heretofore, various designs or configurations of nozzle assemblies have been proposed to provide the above referenced desirable features, particularly the feature that the nozzle assembly be adjustable to provide varying discharge patterns, i.e. a spray pattern and a stream pattern.
Examples of prior art trigger sprayers including an adjustable nozzle cap for selectively dispensing a liquid in a spray mode or stream mode, are disclosed in the following U.S. Pat. Nos.:
______________________________________ U.S. PAT. NO. PATENTEE ______________________________________ 4,767,060 Shay et al. 4,706,888 Dobbs 4,503,998 Martin 4,350,298 Tada 4,313,568 Shay 4,273,290 Quinn 4,247,048 Hayes 4,234,128 Quinn et al. 3,843,030 Micallef ______________________________________ JAPANESE PAT. PUBLICATION NOS. ______________________________________ JP60-183061 JP63-69579 ______________________________________
In U.S. Pat. No. 4,767,060 there is disclosed a nozzle assembly which is capable of selectively dispensing a liquid product as a foam or a spray by means of a selectively movable member to establish a swirl chamber located in between, and in liquid communication with, a passageway and a nozzle outlet orifice. Such member can be moved forward into the nozzle cap where it offers no interference with the vertical liquid sheet to effect a spray mode of delivery. The member can be moved rearwardly to a point where the swirl chamber interferes with the vortical sheet to produce a stream pattern. Gas passageways are provided in this structure to achieve aeration of the turbulent fluid and the resultant dispensing of the liquid as a foam.
U.S. Pat. Nos. 4,706,888; 4,234,128; and 3,843,030 disclose nozzle assemblies each including a rotatable nozzle cap mounted for rotation relative to a cylindrical member, with the cap and member having cooperating radial and/or axially extending passageways for creating stream or swirl liquid flow patterns depending upon the particular registration of the cap with the cylindrical member.
In U.S. Pat. No. 4,706,888 there is disclosed a nozzle assembly capable of being opened and closed in selective rotative positions of a nozzle cap of the assembly with respect to two discreet passages and grooves formed between a discharge conduit and a discharge orifice to provide an alternating off, stream and spray position for a liquid dispenser. Such multiple passages in a cylinder and the nozzle cap cooperate to move in and out of alignment and communication thus providing the spray and stream modes of operation depending upon alignment and registry of the various describe passages and grooves. U.S. Pat. No. 4,706,888 alleges the following drawbacks in the devices disclosed in U.S. Pat. Nos. 3,843,030 and 4,234,128:
"For example, U.S. Pat. No. 3,843,030 has its nozzle cap containing an off-centered discharge orifice which must be shifted upon cap rotation between alignment with the spin chamber at the end of an internal probe for producing a spray, and a channel on the probe for producing a stream. The off center location of the discharge orifice not only presents problems for the consumer in properly targeting the discharge, but gives rise to a shearing action during cap rotation in that the inner edge of the discharge orifice must traverse the plug surface containing the spin chamber and associated tangentials which could cause abrasions or snags between the rotating parts resulting in undue wear and leakage . . . The nozzle assembly of U.S. Pat. No. 4,234,128 like-wise requires the spin chamber and associated tangential grooves to be formed on the underside of the cap end wall, and passages and slots on an internal plug arranged to produce a stream or spray discharge or shut-off. Thus, some of the details for the dispense function are on the cap end wall and some others are on the plug confronting this end wall, such that a shearing action results between these details as they pass one another upon cap rotation. Due to such abrasive and interrupted engagement between rotating parts, scoring, snags and/or undue wear occurs with consequent leakage."
With respect to U.S. Pat. No. 3,843,030 it is observed that the tubular extension described therein includes a free end having a staggered recess for cooperation with the cap in producing spray and stream modes of operation.
The Martin U.S. Pat. No. 4,503,998 discloses a nozzle assembly including an elastic cap-shaped member mounted inside a nozzle cap and having swirl directing channels therein, as well as a swirl chamber. The nozzle cap, spring valve and body assembly of the present invention can be advantageously incorporated into the trigger sprayer disclosed in this patent.
The Tada U.S. Pat. No. 4,350,298 discloses a wave plate spring utilized in a spinner assembly including a cylindrical secondary valve having a rounded end which seats against a valve seat in an outlet passageway in a trigger sprayer. A similar wave plate spring is disclosed in JP 60-183061.
The Shay U.S. Pat. No. 4,313,568 discloses a nozzle assembly for a trigger sprayer wherein the nozzle assembly includes a cap-shaped sealing structure and a disc having holes therethrough and having swirl establishing channels and a swirl chamber in a front surface therein mounted adjacent a front inner wall surface in a nozzle cap.
The Quinn U.S. Pat. No. 4,273,290 discloses a unitary valve and spring assembly for use in a trigger sprayer. The S-spring in this assembly has some similarity with the sinuous spring incorporated into the spring valve and of the nozzle assembly of the present invention.
JP 63-69579 discloses a nozzle assembly including a resilient ring-shaped spring and valve member for use in a nozzle assembly attached to a trigger sprayer.
In U.S. Pat. No. 4,247,048 there is disclosed a two-piece nozzle assembly which features a tubular member having a circular, planar face at its terminal end with a recess in the planar face. When a cap having a dispensing orifice is rotatably mounted to the tubular member it has an end wall with a planar inside surface which will form an interface with the circular planar face of the tubular member. The dispensing orifice of the cap is radially displaced from the center axis of the cap which is registerable, when properly aligned, with the recess of the planar face.